Equipment or HVAC modeling can be used in auto fault detection systems or in energy-efficient applications, including chiller optimization, boiler optimization, occupancy control, or preference-based control. Equipment or HVAC models may contain may components, such as Air Handling Units (AHUs), Variable Air Volume units (VAVs), or diffusers. HVAC systems may have defined control relationships between or among HVAC components, which may define the AHU that supplies specific VAVs, or may define the VAV that supplies specific diffusers. The HVAC system may also define the space in which a VAV is located, or which space is served by a specific diffuser. Given the number and complexity of these relationships, Equipment or HVAC modeling can be complex and time-consuming.